Confronting Iran in a Year of Elections

A DEMOCRATIC president running in a bitterly disputed presidential race faces a fateful national security decision: whether to approve an airstrike to thwart an adversary bent on becoming a nuclear-weapons state.

Conservative hawks deride the president as weak. In the West Wing, advisers debate the risks: a strike could lead to open conflict, but doing nothing would change the balance of power in a volatile, war-prone region.

The president was Lyndon B. Johnson, and less than three weeks before Election Day in 1964, the Chinese rendered the White House discussion moot by setting off their first nuclear test. “China will commit neither the error of adventurism, nor the error of capitulation,” the government of Mao Zedong told the world that morning, heralding the first Asian nation to get the bomb.

Johnson defeated Barry Goldwater in the election anyway, after a campaign in which — oddly enough, given the attack being contemplated — he tarred the Arizona conservative as a warmonger in the infamous black-and-white “daisy” television spot, featuring a young girl counting the petals of a flower, unaware of impending nuclear doom....